BMWcoding has some great guides to get you started. INPA has the instructions located in the folder on your hard drive where it was installed.
You are correct as there is a ton of information out there and a lot of stuff to try and get a handle on.
I think the biggest problem is making sure your cable works. There is a program that will check this for you, and you might need to load some additional drivers to get it all to work.
I went thru this two months ago and the members here will be more than happy to help out with any questions.
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